Substitution products of benzo-



United States Patent Ofiiee 3 ,058,080 Patented Oct. 16, 1962 This invention relates to substitution products of benzo-1,4-oxazine and to various methods of producing them.

More particularly, the present invention relates to substituted benzo-lA-oxazines having the general structural formula wherein wherein Y is hydrogen, aryl, alkyl or ar-alkyl, as well as the corresponding carboxylic salts, esters and amides; or the radical wherein Z is hydrogen or alkyl and n is an integer from to 6, inclusive, X is oxygen or sulfur and R is hydrogen, alkyl, aryl or substituted aryl; or the radical wherein n is an integer from 1 to 6, inclusive, and R and R are hydrogen, alkyl, aryl, aralkyl, substituted aryl, ring-substituted aralkyl and, together with the adjacent nitrogen, 5- to G-membered heterocycles, such as piperidyl, morpholyl, pyrrolidyl, piperazyl and the corresponding substituted heterocycles;

R is alkyl with 1 to 8 carbon atoms, alkenyl with 3 to 5 carbon atoms, aryl, aralkyl, hydroxyalkyl or the radical wherein n is an integer from 1 to 3, inclusive, and R and R have the meanings previously defined; and

R is hydrogen, alkyl with l to 5 carbon atoms, aryl, aralkyl, substituted aryl, ring-substituted aralkyl, hy droxyl, alkoxy, aryloxy, aralkoxy, acyl, tertiary amino, acylamino, sulfonamyl, nitro or halogen;

and their non-toxic, pharmacologically acceptable acid addition salts.

The new compounds according to the present invention may be prepared by methods known per se; more particularly, the following methods have been found to be especially advantageous:

(1) Reaction of a substituted 2-halomethyl-benzo-1,4-

oxazine (II) with a suitably substituted amine (11a) in the presence of an agent which neutralizes a hydrogen halide, according to the following schematic reaction equation: 1 l

4 T 'B1 O CHzHal (Hal=Halogen) 0 GHr-ITI:ZR H-Hal In the formulas of this equation R to R have the previously defined meanings and Hal represents halogen. In the .event that R is hydrogen, it may be exchanged by customary methods prior to the reaction for a radical which may subsequently readily be replaced by hydrogen, such as a benzyl group. This procedure is especially recommended when dealing with delicate amines. The reaction is advantageously carried out by reacting molar quantities of the individual reaction components. Suitable agents for neutralizing the hydrogen halide are, for example, triethylamine or a dialkyl-am'line and the like. In place of a separate agent capable of neutralizing the hydrogen halide, two to three mols of the amine 11a, is. one to two mols excess, may also be employed. The reaction is carried out in the presence or absence of a solvent, such as alcohol, especially ethanol, or hydrocarbons, especially benzene, etc., at temperatures between 20 and 200 C., preferably between and C. Reactions with amines Ila which have a boiling point lower than 80 to 150 C. are preferably carried out in a closed tube.

In the event that in the above reactions an amine Ha is used as one of the reaction components in which R is a hydrogen atom and this hydrogen atom has been exchanged for a radical which is subsequently readily replaceable by a hydrogen atom, this radical is later split off again in such a manner that a secondary amino group is formed.

The production of the previously undisclosed halogen compounds II, which are used as starting materials in the present method, may be accomplished by reacting an o-aminophenol with an epihalogenhydrin to effect ring closure and form the corresponding hydroxy compound III, and transforming this hydroxy compound into the corresponding halogen compound H, for example with a phosphorus oxyhalide, in accordance with the following schematic reaction equation:

l-I- POHalz of neutralizing a hydrogen halide, in accordance with the following schematic reaction equation:

IVa

0 OHzNH-Rn H-Hal In the formulas of this equation substituents R to R and Hal have the previously defined meanings.

' For this reaction of Z-aminomethyl-benzo-1,4-oxazines IV with the halogen compounds IVa, the same conditions apply as those described for process under 1 above.

Primary amines IV which are used as starting materials in this method and which have heretofore not yet been disclosed, may be produced by reacting the corresponding halogen compounds II with ammonia under the conditions described forthe process under 1 above.

(3) Reaction of an o-aminophenol VI with a glycide VII, the hydroxyl group of which has been replaced by the radical of the secondary amine which is to be introduced, whereby this substituted glycide replaces the hydrogen-of the amino group of the aminophenol VI, and subsequent cyclization of the compound Vthus obtained to form compounds of the Formula I, according to the following schematic reaction equation:

0 O Hr-N-Ri In the formulas of the above Equation R to R have the previously indicated meanings. In the event that R is a hydrogen atom, it may be exchanged prior to the reaction for a radical which may subsequently be readily replaced by hydrogen, for example a benzyl group, by

customary methods; This procedure is particularly advantageous in the present method.

The following examples will further illustrate the present invention and enable others skilled in the art to understand it more completely. It will be understood, however, that the invention is not limited to these illustrative examples.

EXAMPLE I (a) Preparation of Starting Compound (Il).4-N- M ethyZ-Z-Chloromethyl-Benzo-I -4-Oxazine 1 mol 4 N-methyl-Z-hydroxymethyl-benzo-1,4-oxazine was added dropwise to 3.5 mol phosphorus oxychloride, accompanied by stirring, and care Was taken by providing suitable cooling means that the reaction temperature remained below the boiling point of the phosphorus oxychloride. After all of the benzo-l,4-oxazine compound had been added, the reaction mixture was heated for one more hour at the boiling point in order to cause the reaction to go to completion. The excess phosphorus oxychloride was then distilled oif in vacuo at a bath temperature of C. The residual raw reaction product was then further reacted in this form with the desired amine IIa without intermediate purification.

If relatively expensive amines Ila are used for the subsequent reaction, it is recommended to employ the free, pure 4-N-methyl-2-chloromethyl-benzol,4 oxazine. In order to obtain the pure product, the raw product is added, accompanied by stirring andintermittent cooling, to 400 cc. S-N-sodium hydroxide which has a layer of 200 cc. benzene onits surface. After removal of the benzene from the organic phase, the free chloride is distilled oif and is obtained in the form of a faintly yellow oil having a boiling point of 156 C. at 12 mm. Hg. Structural formula:

(b) Preparation of 4-N-Methyl-2-Butylamin0methyl- Banza -1 ,4-Qxazine A mixture of 198 gm. 4-methyl-2-chloromethyl-benzo- 1,4-oxazine and gm. bntylamine was heated in a closed tube for six hours at 120? C. After allowing the contents of the'tube to cool, they were made alkaline with 5 N sodium hydroxide and the resulting solution was exhaustively extracted with ether. The combined dried ether extracts were concentrated by evaporation and the residue methyl-benzo-1,4-oxazine and phosphorus oxychloride according to the method described in Example Ia) and 300 gm. N,N-dimethylethylene diamine was refluxed for eight hours. The reaction mixture was then worked up as described in Example Ib. The product, having the structural formula 1115 CHOHzNHCH2CH2 and a boiling point of 209-211 C. at 12 mm. Hg, Was obtained in the form of a colorless oil; yield: to of theory.

The following table lists additional substituted benzo- 1,4-oxazines of the Formula I which were produced by method Ib above, i.e. reaction of a compound of the Formula II with an amine of the Formula 11a. The table shows the identity of the starting materials, the meaning of substituted R through R; in the end product of the Formula -I and, under the heading Properties, the boiling point of the end product and in some instances the melting point of the corresponding hydrochloric acid addition salt.

Ex. No.

Starting materials End product (Formula I) Properties Free base Hydrochloride M P Atmm.

4-N-methyl-2-ch1oromethylbenzo-1,4-oxazi.ne and morpholine.

4-N-methyl-2-chlororuethylbenzo-1,4-oxazine and N,N- diethylethylene-diamme.

4-N-methyl-2-chloromethylbenzo-1,4-oxazine and n-propylamine.

4-N-methyl-2-chloromethyl- ,benzo-lA-oxazine and ethanolamine.

4-N-methyl-2-eh1oromethylbenzo-1,4-oxazine and N ,N- dimethyl-ethylene-diamine.

4-N-methy1-2-chlorornethylbenzo-lA-oxazine and N,N- dimethyl-propylenediamine.

4-N-ethyl-2-chloromethylbenzo-lA-oxazine and N,N- dimethyl-propylenediamine.

4-N-ethyl-2-chloromethylbenz0-1,4-oxazine and ethanolamine.

4-N -ethy1-2-ehloromethy1- benzo-1,4-oxazine and N,N- diethylethylenediamine.

4-N-(B-morpholyI-ethyD-2- chloromethyI-benzo-IA- oxazine and morpholine.

4-N-methyl-2-ch1oromethylbenzo-1,4-oxazine and npropanolamine.

g-N-methyl-Z-chloromethyk benzo-1,4-oxazine and 1S- hydroxy-propylamiue.

4-N-methyl-2-chloromethy1- benzo-1,4-oxazine and methoxy-propylamme.

n-CaH1 -CE PCHrO-CHPOHz- CH H 0. 01 232-235 CH3 H 162-165 0. 1 -178 CHa H -185 12 180-185 CH3 H 225-230 12 180-183 OH: H 205-207 12 170 CH3 H 210-215 12 180-185 CzH H 224-227 12 166-167 CH: H 235-240 12 CH3 H 225-230 12 215-218 CHa H 210-215 12 154-158 The substituted benzo-1,4-oxazines having the aboveindicated Formula I exhibit useful pharmacodynamic properties. More particularly, they exhibit analgesic activities and prolong the barbiturate sleep.

The following statements are related to 4-N-ethyl-2- (methylamino-methyl)-benzo-1,4-oxazine, which is the compound according to Example 17, 4-N-ethyl-2-(butylamino-methyl)-benzo-1,4-oxazine, which is the compound according to Example 18, and 4-N-ethyl-2-[(,B-hydroxy- ,B-methyl)-ethyl]-benzo-1,4-oxazine, which is the compound according to Example 19.

The individual effective dose of those compounds is from 30 to 200 mgm. Individual doses of 40 to 80 mgm. are preferred. These individual doses should be administered one to three times a day.

The compounds in accordance with the present invention may be administered in dosage form by means of diverse compositions, such as tablets, sugar-coated pills, capsules, ampoules, suppositories, drops or the like.

The following examples will illustrate various compositions adapted for internal administration of the compounds in accordance with Examples 17, 18 and 19 above in dosage form.

EXAMPLE 83 TABLETS 1 tablet contains:

4 N-ethyl-2-(methylamino-methyl)-benzo-1,4-

oxazine 50.0 See. calcium phosphate 40.0 Milk sugar 70.0 Potato starch (dry) 40.0 Soluble starch (APS-starch) 5.0 Talcum 13.0 Magnesium stearate 2.0

The 4 N-ethyl-Z- (methylamino-methyl) -benzo-1,4-oxazine and the calcium phosphate are granulated with 80% alcohol by passing through a screen having a mesh width of 1 mm., and are then dried at 45 C. The milk sugar and the potato starch are granulated with 15% APS-starch by passing through a screen having a mesh width of 1 mm., and are then dried at 45 C. The dried granulates are admixed with the remaining adjuvant substances and pressed into tablets having a diameter of about 9 mm.

EXAMPLE 84 SUGAR-COATED PILLS The 4 N-ethyl-Z-(butylamino-methyl)-benzo-1,4-oxazine, the milk sugar and potato starch (dry) are mixed together. The mixture is kneaded thoroughly with a 10% aqueous gelatin solution. The moist mass is granulated by passing through a screen having a mesh width of 1.5 mm., and is then dried at a temperature of 45 C. The dried granulate is admixed with magnesium stearate 14 and potato starch. The mixture is pressed into tablets having a weight of 220 mgm. and a diameter of 9 mm.

EXAMPLE 86 SUGAR-COATED PILLS The tablets prepared in accordance with Example are coated with a thin shellac coating and are then coated in known manner with sugar sirup to form the pills.

EXAMPLE 87 CAPSULES 1 capsule contains:

Mgm

4 N- ethyl-2-[(B-hydroxy-fi-methyl)-ethyl]- benzo-1,4-oxazine 60.0 Milk sugar 60.0 Talcum 10.0

The substances are mixed together and filled into gelatin capsules of suitable size.

EXAMPLE 88 1 suppository contains:

4 N ethyl 2- (methylamino-methyl)-benzo-1,4-oxazine 80.0 Suppository mass (Witepsol H) 1,620.0

The finely powdered 4-N-ethyl-2-(methylamino-methyl)-benzo-1,4-oxazine having a particle size of less than 100 ,u. is added to the suppository mass which has been melted at 37 C. The mass is cooled with stirring to 34 C. and poured into precooled suppository molds of corresponding size.

EXAMPLE 90 DROPS 4 N- ethyl-2-(butylamino-methyl)-benzo-1,4-oxazine 4.0 p-Hydroxy-methyl benzoate 0.035 p-Hydroxy-propyl benzoate 0.015 Ethanol (pure) 10.0 Saccharin-sod 1.0 Glycerin 15.0

Aromatic (e.g. Bitteressenz No. 25973 Haarm. &

Reimer) 3.0

Distilled Water, ad ccm.

1 ccm. contains 40 mgm. 4-N-ethyl-2-(butylamino-methy] benzo-1 ,4-oxazine. The p-hydroxy benzoic esters and the aromatic are dissolved in ethanol. The saccharin-sod. and the 4-N- ethyl 2 (butylamino methyl) benzo 1,4 oxazine 15 are dissolved in water. The two solutions are mixed'together, and the glycerin is addded thereto. The resulting solution is filtered until clear.

It is obvious that the compounds according to Examples 17, 18 and 19 are used merely as illustrative active ingredients in Examples 83 through 90 and maybe replaced by any of the other substituted benzo-1,4- oxazines embraced by Formula I.

Since the compounds according to the present invention comprise at least one amino group attached to the side chain in the 2-position, they may readily be converted into non-toxic, pharmacologically acceptable acid addition salts by customary methods. In addition to the hydrochloric acid addition salts, Which are illustrated in the above examples, other non-toxic, pharmacologically acceptableacid addition salts are, for example, those formed with hydrobromic acid, sulfuric acid, phosphoric acid, acetic acid, tartaric acid, ascorbic acid and the like.

While I have illustrated by invention with the aid of certain specific embodiments thereof, it will be readily apparent to others skilled in the art that the invention is not limited to these particular embodiments and that various changes and modifications may be made without departing from the spirit of the invention or the scope of the appended claims.

What I claim is:

1. Compounds selected from the group consisting of substituted benzo-l,4-oxazines of the formula wherein 7 R is selected from the group consisting of hydrogen and, together with R and the adjacent nitrogen atom, morpholyl, piperid'yl and N-phenyl-piperazyl,

R is selected from the group consisting of lower alkyl, hydroxy-lower alkyl, lower alkyl-amino-lower alkyl, lower alkoxy-lower alkyl, phenyl-lower alkyl and lower alkenyl,

R is selected from the group consisting of lower alkyl, lower alkyl-amino-lower alkyl, morpholyl-lower alkyl and (N-lower alkyl-lower 2lkylene-diaminn\- lower alkyl, and

R is selected from the group consisting of hydro en.

halogen and lower alkyl,

and their non-toxic, pharmacologically acceptable acid addition salts.

2. 4 N ethyl 2 (methylaInino-methyl) bemo- 1,4-oxazine.

3. 4 N ethyl 2 (butylamino methyl) benm- 1,4-oxazine.

4. 4 N ethyl 2 [(1 hydroXy ,8 methyl)-ethyl] benzo-1,4-oxazine.

5. 4 N ethyl 2 (propylamino methyl) benzo- 1,4-0Xazine.

6. 4 N methyl 2 (methylamino methyl) -benzo- 1,4-oxazine.

7. 4 N propyl 2 (morpholyl methyl) benzo- 1,4-oxazine.

8. 4 N ethyl 2 [(fi N,'N dimethylamino-ethyl)- amino-methyl] -b enzo- 1 ,4oxazine.

No references cited.

:UNITED STATES PATENT @FFIQE CE'HFICATE F CQRRECTIN Patent No, $058,980 October 16 1962 Alex Berg It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2, lines 64 and 65 for that port-ion of the formula reading v il read F column 13, line 62 for "ozazine" read oxazine column V 15, line 19, for "105 read my Signed and sealed this 19th day of March 1963.

(SEAL) Attest:

esrom G, JOHNSON I DAVID DD Commissioner of Patents Attesting Officer I 

1. COMPOUNDS SELECTED FROM THE GROUP CONSISTING OF SUBSTITUTED BENZO-1,4-OXAZINES OF THE FORMULA 